1. Technical Field
The present disclosure relates to methods and systems for carbon dioxide (CO2) separation. More particularly, the present disclosure relates to methods and systems for sorbent-based CO2 separation.
2. Discussion of Related Art
Power generating processes that are based on combustion of carbon containing fuel typically produce CO2 as a byproduct. It may be desirable to capture or otherwise separate the CO2 from the gas mixture to prevent the release of CO2 into the environment and/or to utilize CO2 in the power generation process or in other processes.
However, typical CO2 capture processes, such as, for example, aqueous amine-based process may have limitations, for example, the process can sometimes result in sharp increases in the viscosity of the liquid absorbent, which can decrease the mass transfer of CO2 into the sorbent. To avoid this problem, the concentration of amines in the absorbent stream may be maintained at low levels (using carrier solvents), which may greatly reduce absorbing capacity, as compared to the theoretical capacity of the neat absorbent. Moreover, energy consumption in the amine process may be high, due in large part to the need for heating and evaporation of carrier solvent (for example, water). Another example of a commercial CO2 post-combustion capture process may use aqueous solutions of piperazine-promoted potassium carbonate (K2CO3) that has disadvantages similar to the amine process because of the additional solvent. Further, this process is often very energy-intensive, and may be economically inferior to the amine process.
Thus, there is a need for efficient methods and systems for separation of CO2. Further, there is a need for efficient methods and systems for sorbent-based separation of CO2.